Group symbols assigned to silty sand and clayey sand are respectively
In a BOD test using 5% dilution of the sample (15 ML of sample and 285 mL of dilution water), dissolved oxygen values for the sample and dilution water blank bottles after five days incubation at `20^circ`C were 3.80 and 8.80 mg/L. respectively. Dissolved oxygen originally present in the undiluted sample was 0.80 mg/L. The 5-day `20^circ`C BOD of the sample is
A footing 2 m x 1 m exerts a uniform pressure of 150 kN/m2 on the soil. Assuming a load dispersion of 2 vertical to 1 horizontal the average vertical stress (kN/m2) at 1.0 m below the footing is
Two completely penetrating wells are located L (in metres) apart, in homogeneous confined aquifer. The drawdown measured at the mid point between the two wells (at a distance of 0.5 L from both the wells) is 2.0 m when only the first well is being pumped at the steady rate of Q1 m3/sec. When both the wells are being pumped at identical steady rate of Q2 m3/sec, the drawdown measured at the same location is 8, 0 m. It may be assumed that the drawdown at the wells always remains at 10.0 m when being pumped and the radius of influence is larger than 0.5 L Q1/Q2 is equal to
Flow at critical depth takes place in an open channel When